We’ve all known for a good while now that cartoons aren’t just for kids anymore. In fact, unless you’ve been having a decade-long love affair with Ingmar Bergman retrospectives, you might have noticed that, thanks largely to the growth of Japanese style animation, cartoons are so insanely violent that they make George Romero look like a whimpering sissy.

The Happy Tree Friends DVD looks like your average cuddly sweet nonsense about big-headed, big-eyed freaky little animals, until you notice the title says “Episode 1: First Blood,” and when you open up the box you get to admire a hollow tree stump full of dismembered cute widdle fuzzies. Put out by syndicated webtoon divas Mondo Mini Shows (www.mondominishows.com), “Happy Tree Friends” was an instant hit on the Internet. Many a sick little monkey has enjoyed a dirty giggle at the sight of Toothy the Beaver doing gymnastics with his optic nerve, or Cuddles the rabbit exploding in a shower of blood.

With its shrill theme song, sickeningly cute voices and endless supply of way, way over-the-top gore, “Happy Tree Friends” is more than just stupidity and blatant perversion. It’s funny, too: The comic timing is superb, and it’s a real art to make reliable comedy out of brains popping out of eye sockets. You know it’s coming, you know it’s stupid, and yet you laugh anyway. If you watch the Simpsons just for “Itchy & Scratchy,” these are your dream come true.

Kenn Navarro and Rhode Montijo started drawing “Happy Tree Friends” about three years ago, when Montijo discovered he was not alone in being a twisted, deeply violent geek with an interest in cartoons. He joined forces with Navarro and began producing the short cartoons that quickly became the star of the Mondo lineup. Mondo is a persistent battler in the internet arena, surviving the dot-bomb and continuing to produce such enlightening fare as “Zombie College” and “Hard-Drinkin’ Lincoln.”

The DVD is more than a collection of the webtoons, which anybody can see for free. Highlights include an amusing look at the evolution of a cartoon character, from archaic “Steamboat Willie” types to the current cross between Bullwinkle and Pokemon. Navarro and Montijo don’t make any excuses for their art, but they love to talk about it. The outtakes are priceless. This reviewer almost busted a gut listening to Giggles the Bear laconically explain (in a real human voice) how they had to do thirty-five takes of her disembowelment and impalement on a tree stump, and “it was a really great experience,”

It’s this tongue-in-cheek demeanor that makes stuff like this work. Without the certainty that all of these vomit-worthy gorefests are self-informed, poking fun at themselves as they joust at larger targets, it would get boring really fast. Remember “Frog in a Blender”? That was only funny the first two hundred times, and now it’s old, old, hat.

Navarro and Montijo constantly reinvent their medium, the cute little animal psycho murder cartoon, stretching gags way past their breaking point and adding in clever details to prove their brains are still switched on. For instance, the first webtoon, “Spin Fun Knowin’ Ya” is just your classic mayhem and gore distinguished only by the nifty view angles and dynamic action plotting. But by the time you view “Crazy Antics,” you see Sniffy the Anteater’s tongue shanghaied by a nuclear family of suburban ants sitting down at the dinner table, a gleeful twist on the strong bullying the weak.

Without that kind of existential self-referential auteur-ism, these webtoons would be nothing but insanely violent cartoon murder set to a catchy children’s tune. If that’s what you’re looking for, then annoy your coworkers/roommates by watching them at top volume. If you want to show off your geeksmanship and hear two jolly nutcases talk about the process of making a cult hit, then spring for the DVD; it’s well worth it.